[PATCH v13 05/10] drm/mediatek: Add MT8195 Embedded DisplayPort driver

CK Hu ck.hu at mediatek.com
Wed Jul 6 19:35:13 PDT 2022


Hi, Bo-Chen:

On Fri, 2022-07-01 at 14:28 +0800, Bo-Chen Chen wrote:
> From: Markus Schneider-Pargmann <msp at baylibre.com>
> 
> This patch adds a embedded displayport driver for the MediaTek mt8195
> SoC.
> 
> It supports the MT8195, the embedded DisplayPort units. It offers
> DisplayPort 1.4 with up to 4 lanes.
> 
> The driver creates a child device for the phy. The child device will
> never exist without the parent being active. As they are sharing a
> register range, the parent passes a regmap pointer to the child so
> that
> both can work with the same register range. The phy driver sets
> device
> data that is read by the parent to get the phy device that can be
> used
> to control the phy properties.
> 
> This driver is based on an initial version by
> Jitao shi <jitao.shi at mediatek.com>
> 
> Signed-off-by: Markus Schneider-Pargmann <msp at baylibre.com>
> Signed-off-by: Guillaume Ranquet <granquet at baylibre.com>
> Signed-off-by: Bo-Chen Chen <rex-bc.chen at mediatek.com>
> ---
> +
> +static void mtk_dp_power_enable(struct mtk_dp *mtk_dp)
> +{
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_RESET_AND_PROBE,
> +			   0, SW_RST_B_PHYD);
> +
> +	/* Wait for power enable */
> +	usleep_range(10, 200);
> +
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_RESET_AND_PROBE,
> +			   SW_RST_B_PHYD, SW_RST_B_PHYD);
> +	mtk_dp_update_bits(mtk_dp, MTK_DP_TOP_PWR_STATE,
> +			   DP_PWR_STATE_BANDGAP_TPLL,
> DP_PWR_STATE_MASK);
> +	mtk_dp_write(mtk_dp, MTK_DP_1040, 0x7);

You have define the bit definition. Use the bit definition instead of a
magic number.

+#define MTK_DP_1040			0x1040
+#define RG_DPAUX_RX_VALID_DEGLITCH_EN	BIT(2)
+#define RG_XTP_GLB_CKDET_EN		BIT(1)
+#define RG_DPAUX_RX_EN			BIT(0)

> +}
> +




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